shutter

/ˈʃʌtə/

noun

1.

a hinged doorlike cover, often louvred and usually one of a pair, for closing off a window

2.

put up the shutters, to close business at the end of the day or permanently

3.

(photog) an opaque shield in a camera that, when tripped, admits light to expose the film or plate for a predetermined period, usually a fraction of a second. It is either built into the lens system or lies in the focal plane of the lens (focal-plane shutter)

4.

(photog) a rotating device in a film projector that permits an image to be projected onto the screen only when the film is momentarily stationary

5.

(music) one of the louvred covers over the mouths of organ pipes, operated by the swell pedal